Philosophical Psychopathology

Philosophy without Thought Experiments

G. Young

• Publisher: Palgrave Macmillan
• Year: 2013
• Print ISBN: 9781137329318
• eBook ISBN: 9781137329325
• Topic: Psychology
• Subtopic: Mind & Body in Philosophy
• Index: Psychology

This book uses rare pathologies to inform questions on topics such as consciousness and rationality. Rather than trying to answer these by inventing far-fetched scenario or 'thought experiments', it is better to utilize a rich but under-used clinical resource.

1

Introduction

In this chapter I explain what is meant by the term philosophical psychopathology, what thought experiments are and what their role has been (and continues to be) within the philosophical tradition. I then move on to outline the book’s aim which is to show how, in light of the growing availability of case study evidence documenting rare human pathological conditions and our ever-increasing neurological understanding of how the brain works, it is possible to engage with certain philosophical issues in the absence of thought experiments. It is not therefore my contention that thought experiments have no place in philosophy; rather, I aim to show only that pathological case study evidence amounts to a rich but, at present, underused resource, and that this resource merits a more prominent role within philosophical inquiry.

1.1 What is philosophical psychopathology?

Philosophical psychopathology is the ‘investigation of philosophical issues arising from consideration of various sorts of mental disorders’ (Graham & Stephens, 1994, p. 4): for such is the peculiar and divergent nature of psychopathological phenomena that they constitute a valuable tool for use in contemporary philosophical research. Again, in the words of Graham and Stephens:

Some of the most arresting and puzzling phenomena described in the clinical literature on psychopathology are the disturbances of self-consciousness that frequently accompany, and sometimes seem to constitute the essence of, various mental disorders ... Though one would suppose that these ... would represent an invaluable theoretical resource, they have seldom been exploited in traditional philosophical accounts of human mentality. Fortunately, this surprising gap between clinical observation and philosophical theorizing has been closing dramatically in recent years. (1994, p. 1)

Philosophical psychopathology, as the name suggests – and as Graham and Stephens describe – uses as a substantial resource for philosophical inquiry various forms of mental disorder. These psychopathologies include delusional states such as the Capgras and Cotard delusions, as well as delusions of control such as thought insertion. Yet in addition to these psychopathologies, this book discusses pathologies of the brain which are not held to be (crudely speaking) forms of mental illness. Someone suffering from anarchic hand, for example, may say of their hand when ‘behaving’ in an uncontrollable way – “It is as if it has a will of its own” – but this does not mean that the patient actually believes that the hand is being controlled by another’s will. In other words, these patients are not delusional. Compare this to a condition known as alien control in which the patient believes that someone else is controlling their movements and therefore that another’s agency is being expressed directly through their actions. Here, the patient is judged to hold a delusional belief.

Both cases are examples of pathologies, and each is unusual and even bizarre in its own right, but only the latter should be construed as psychopathological. Case studies involving often unusual and bizarre pathologies (whether psychopathological or not) provide a constant source of data which act to stimulate pertinent philosophical questions and perhaps challenge (although they may support) traditional or contemporary theories and conceptualizations. In fact, such is the peculiarity of these pathologies that they resemble in many ways concrete examples of the kinds of hypothetical circumstances that feature in philosophical thought experiments.

1.2 What is a thought experiment?

Thought experiments tend to begin with the word “Imagine”, or certainly lend themselves to such a beginning. Imagine a world exactly like our own except for a difference in the chemical composition of water, for example. Or imagine that your brain is transplanted into the body of another without a brain, or that one day lightning strikes a dead tree in a swamp which results in the creation of a physical replica of yourself called Swampman, and so on. Thought experiments are in a sense imaginings, but if they are to be successful as thought experiments then they are imaginings constrained by conceivability and so by logical necessity. They are suppositions intended to support or more likely challenge a particular theory or conceptualization; but, in doing so, they are bound by the same rules of logic, the same dependence on conceivability, said to be at fault within the theory or concept under scrutiny.

Importantly, then, for a thought experiment to be conceivable it must not be conceptually confused or contradictory. To illustrate: it is not legitimate (as a thought experiment) to say “Imagine a four-sided triangle” because it is not conceivable that such an object could exist. What we refer to as a triangle necessarily has three sides (no more, no less; or three-angles to be precise, which we equate with having three sides). Similarly, given that the word ‘all’ is understood to mean ‘completely’ or ‘in its entirety’ or ‘the total number’, it is illegitimate to “Imagine being at the same time all black and all white”: for it is a logical contradiction that one could be entirely one thing and entirely another.

One of the oldest recorded thought experiments concerns the universe and the concept of infinity (found in Lucretius’ De Rerum Natura [The Nature of Things]). It asks us to consider whether there is a boundary to the universe. That is, whether it is finite or infinite. Even now, as was certainly the case in the ancient world (from where this thought experiment originated), we are unable to test this supposition directly through empirical methods (for example, by travelling in search of the end point, should it exist). Nevertheless, it may be that an answer can be postulated through a priori reasoning alone. If the universe (conceived to mean ‘all that there is’) is finite then there must be an end: a cosmic boundary. So begins the thought experiment: Imagine that there is what looks like some form of cosmic boundary. If one were to throw a spear at it then logic dictates that one of two possibilities should arise: either the spear would pass through the boundary or it would be repelled (to bring the example up-to-date, one might replace the spear with a laser or phaser blast). If the former, then the cosmic boundary does not signify the limit of the universe, as the spear is able to continue past it into something else and therefore the universe is not all there is. If the latter is the case, and the spear is repelled (or even disintegrates), then there must be something on the other side of the boundary. Either way, the thought experiment (as conceived) leads us to conclude that the universe is not finite and so must be infinite.

Thought experiments must adhere to what is logically possible, otherwise any theory or concept within a theory cannot easily be undermined by them. Based on how we conceive of a bachelor, for example, it would be hard to defend the claim that all bachelors are unmarried men if one were allowed to say with any credence “Imagine a married bachelor”. Likewise, there is no logical contradiction in saying that Fred Bloggs is awake or that he is asleep, but it would violate the rule of contradiction to say Fred Bloggs is awake asleep, at least based on how we conceptualize these two terms individually. As such, we could not imagine being awake asleep because this is not something we can conceive clearly ‘in the mind’. David Hume (1739–1740; 2007) makes essentially the same point when conceiving of a mountain:

‘Tis an establish’d maxim in metaphysics, That whatever the mind clearly conceives includes the idea of possible existence, or in other words, that nothing we imagine is absolutely impossible. We can form the idea of a golden mountain, and from thence conclude that such a mountain may actually exist. We can form no idea of a mountain without a valley, and therefore regard it as impossible. (§32; emphasis in original)

Our conception of a mountain does not negate a mountain of gold. What is does prevent is that a mountain could exist in the absence of a valley: the former necessitates the latter. Therefore, we could not clearly conceive of this in our imagination and so it is impossible. What this last point illustrates is that a lack of conceptual clarity through logical contradiction is not the only thing a successful thought experiment must guard against; there is also the issue of metaphysical possibility.

To help illustrate this, in the next section we consider Saul Kripke’s famous example – “Water is not H₂O” (Kripke, 1980) – alongside other contemporary thought experiments.

Examples of contemporary thought experiments

Kripke’s statement – water is not H₂O – is not a logical contradiction because there is nothing within our conceptual understanding of water that means (a priori) it is necessarily identical to H₂O. Compare this to “A bachelor is not an unmarried man” which is a logical contradiction because, as already noted, our (a priori) conceptual understanding of bachelor means it is necessarily identical to an unmarried man. Instead, Kripke’s example contradicts what is metaphysically the case, because it is metaphysically the case that water is H₂O (it is a discoverable fact which is why Kripke calls the identity relation a posteriori necessary). To say “Imagine water is not H₂O” is to imagine what is not metaphysically possible. As with contradicting what is logically possible, a thought experiment that violates what is metaphysically possible would likely be considered problematic.

Hilary Putnam’s twin Earth thought experiment does, however, ask us to imagine an identical Earth which differs from our own only insofar as what is called water on twin Earth has the chemical composition XYZ and not H₂O (Putnam, 1975). This example does not violate what is metaphysically possible because Putnam is not saying that the substance we call water on Earth is not H₂O, only that what is called water on twin Earth (a different substance) is not H₂O. In creating this thought experiment, Putnam is interested in how one arrives at the meaning of the word ‘water’ on Earth and twin Earth, respectively.

Finally, consider the philosophical zombie (a creature we will discuss in more detail in Chapter 2). The philosophical zombie requires that we imagine a creature identical to ourselves in every way except that it has no phenomenal consciousness. There is nothing-it-is-like¹ for the creature to experience the aroma of coffee, for example, or the taste of chocolate, or the painfulness of pain. Such a creature does not exist in this world (as far as we know!). But is this fact just a contingent fact (insofar as it just happens to be the case that it does not exist here but need not have been)? In other words, does such a thought experiment violate only what is nomologically possible in that it violates the laws of nature (which it could be argued are contingent) and not what is metaphysically possible? In conceiving the possibility of philosophical zombies, one requires only that (given the putatively contingent laws of nature), there could be some other world where they exist. The impact of this possibility on the doctrine of physicalism will be explored more fully in the ensuing chapters.

What role do thought experiments play?

If one’s imaginings do not lend themselves to logical contradiction or violate what is metaphysically possible, then such imaginings, in the guise of thought experiments, are held by many to be a useful tool which enables philosophers (and others) to examine accepted conceptualizations and theory and, if necessary, demand that we re-think them. Thought experiments in philosophy are designed to teach us about how we conceptualize reality – or the nature of a thing – a priori, so that we might learn without recourse to experience by simply thinking about it logically. Consequently, thought experiments do not limit our conceptual understanding to what is (meaning: what is empirically shown to occur in this world and therefore what happens to be the case, here and now); rather, they allow and in fact demand, where appropriate, that any such understanding include what could be the case in all possible worlds (if this is relevant to the theory or concept under scrutiny, or course). As such, even if something is shown to be the case in this world – say, that mental states arise out of lumpy grey matter (to borrow David Chalmers’ phrase) and/or that consciousness is a function of neuronal processing – do these ‘facts’ remove the (metaphysical) possibility that consciousness could arise from the functioning of something other than neurons? In simple terms, is it clearly conceivable that a physical system other than a brain could give rise to consciousness? Known facts do not eradicate the need, and therefore the value, of thought experiments.

A cautionary note

The philosopher Daniel Dennett is somewhat critical when it comes to the use of thought experiments. He argues that they tend to serve as intuition pumps (Dennett, 1991) by acting as an elaborate narrative which bolsters our intuitions about how the world is. Such storytelling, Dennett cautions us, however entertaining or intuitively compelling it may be, should not replace a sound argument (which is presumably empirically based). Similarly, Katherine Wilkes holds that thought experiments can be and often are misleading, because the author (of the thought experiment) does not provide sufficient background information to fully inform the reader and therefore to fully determine the coherence of the example and the phenomenon used within it. First she states:

The burden of any thought experiment rests on the establishment (in the imagination) of a phenomenon. Once the phenomenon is established, the inference to a theory is fairly unproblematic; that is, the jump from data to theory is relatively small ... [I]f we got the phenomenon right then the theory followed more or less automatically. (Wilkes, 1988, p. 8; emphasis in original; cited in Sommers, 2002, p. 4)

She then adds a word of caution: where there is uncertainty brought on by a lack of detail or clarity of description then it is not, nor can it be, clear whether the thought experiment has succeeded in establishing the phenomenon to be used. This being the case:

[O]ur intuitions run awry, and the inferences are not only problematic, but the ‘jump’ from the phenomenon to the conclusion is made the larger because of the further need to imagine just what these backing conditions, under the imagined circumstances, would be. The ‘possible world’ is inadequately described. (ibid.)

1.3 The aim of this book

Despite what the title may be taken to imply, or the cautionary words of Dennett and Wilkes, it is not an aim of this book to advocate that philosophers abandon thought experiments altog...

Table of contents

• Cover
• Title
• 1 Introduction
• Part I   The Role of Consciousness in Intentional Action
• Part II   Thought, Subjectivity and Rationality
• Part III   Knowledge How and Epistemological Reduction
• References
• Index